Sleep Apnea Syndrome (SAS) patients cause traffic accidents or industrial accidents in several times higher probability than healthy human. SAS is related to remote causes of sudden death by hypertension, myocardial infarction, and/or cerebral apoplexy. Prevalence of SAS is 4% and in Japan, 2 millions of SAS patients are reported and 2.8 millions of potential SAS patients exist. Polysomnography (PSG) is used for diagnosis of SAS. PSG is an elaborate system and therefore non-invasion screening measurement devices are needed for SAS patients. We have developed a SAS sensor using plastic optical fiber (POF) and we have reported that the POF-SAS sensor has high sensitivity to sense the presence of respiration. This paper reports the development of a portable new POF-SAS sensor and the results of measurement for an ailment patient of SAS.